This renames the core file to rtl8xxxu_core.c in order to allow us to
keep the module nake rtl8xxxu.ko when refactoring the code into
multiple files.
Signed-off-by: NJes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: NKalle Valo <kvalo@codeaurora.org>